An article in the October 2020 edition of Stormwater magazine titled "From Gray to Green to Smart" stood out for its succinct review of the state of stormwater management to date and its primer on an exciting new prospect for future management.
The beginning of the article recounts how stormwater management has remained relatively unchanged for 6,000 years. Stormwater, and often wastewater, is/was collected in pipes or ditches and directed to nearby streams or waterbodies. Bates describes how London passed the original clean water act in the 14th Century and how humanity struggled to effectively manage wastewater and stormwater for the next 500 years.
The article skips ahead to the 1970s when pressure related to land use and land value came into conflict with fire regulations. Curb and gutters found their way into the suburbs replacing traditional stormwater ditches in an effort to reclaim precious square footage for homeowners. The effect was a decrease in the time of concentration for the peak discharge of storm events which resulted in flash flooding, stream bank erosion, and ironically property loss.
The article pivots to the 1990s and the realization that a changing climate was going to reveal the looming crisis that "The decisions made over the past 200 years concerning stormwater management would soon be exposed as insufficient."
Batts proceeds through the rise of green stormwater infrastructure (GSI or GI) in the 2000s as a method of stormwater management that seeks to return to a nature-like system with decentralized landscape-based management facilities.
The crux of the article comes with the introduction of smart technology being applied to stormwater management systems. A flood control pond equipped with telecommunications capabilities, some automated technology, and monitored by a computer or human could respond in real time to weather forecasts. This smart pond could drain down in a controlled manner in advance of an impending storm event thereby providing capacity for the expected runoff.
Luckily, this future already exists in its infancy. The Centric apartment project on the border of Uptown and Little Italy in Cleveland has incorporated this smart technology into its stormwater management system. The Centric collects stormwater runoff into a cistern that is ordinarily used to irrigate the landscaping. When a storm event is forecast the automated valve opens and slowly releases the stored water in a controlled manner over an extended period. This slow release prevents the receiving sewer pipes from flooding. When the rain finally falls the now empty cistern has its full volume available to collect the runoff, again protecting the receiving sewers from flooding.
While I have attempted to provide a comprehensive summary I highly recommend reading the full article and envisioning what the future may bring. In a year where there were so many tropical storms that National Hurricane Center had to resort to the Greek alphabet for additional names Batts' thesis rings true...smarter stormwater management is needed.
Blog Author: Brent Eysenbach, Senior Program Manager